1. Field of the Invention
The present invention relates, in general, to caps for bottles which contain a variety of materials, such as drinks, liquid medicines or liquid chemicals, therein and, more particularly, to a cap device for such bottles, which is capable of mixing an additive contained therein with a material contained in a bottle to prepare a mixture in accordance with a simple rotating action of the cap device relative to the bottle, performed by a user, thus allowing the user to easily prepare the mixture just before taking or using the mixture.
2. Description of the Related Art
In the prior art, most of conventional disposable bottles circulated and sold in markets each contain therein only a single kind of material, such as a drink, a liquid medicine or a liquid chemical, and are closed by caps at mouths thereof. When a user wants to add an additive to the material contained in such a capped bottle so as to prepare a mixture prior to taking or using the mixture, the user must add the additive from a separate container to the bottled material after removing a cap from the bottle. Therefore, it is necessary for manufacturers of the additives and the bottled materials to separately contain such additives and materials in separate containers and bottles prior to marketing them, thus undesirably wasting natural resources due to the production of the separate containers and capped bottles. In addition, the adding of the additive from the separate container to the bottled material to mix them after removing the cap from the bottle is inconvenient to the user in that the user is forced to separately purchase and handle the additive container and the bottle. Furthermore, there is a likelihood that the additive may leak or spill during the mixing process and fall onto the user's body or garment.
Also, it is difficult for the user to add a precise amount of the additive from the separate container to the material contained in the bottle, and so the user ends up roughly measuring the amount of the additive to be added to the bottled material. Therefore, in the case of mixing of an additive with a bottled drink to produce a mixed beverage, the rough measurement of the amount of the additive may result in change in taste and quality of the mixed beverage. In the case of mixing of an additive with a bottled liquid medicine or a bottled liquid chemical to produce a mixed medicine or a mixed chemical, the rough measurement of the amount of the additive may result in incomplete dissolution of effective ingredients of the additive in the medicine or the chemical and a failure of accomplishment of desired medical or chemical effects of the mixed medicine or the mixed chemical.
Of course, when mixtures are prepared by manufacturers at factories and are marketed in a bottled state, in place of allowing users to mix additives with bottled materials to prepare mixtures just before taking or using the mixtures, it is possible to avoid the above-described problems experienced in the mixing of the additives with the bottled materials performed by the users. However, the mixtures which are prepared by the manufacturers and marketed in the bottled state are problematic in that the effects of ingredients of the bottled mixtures may be gradually degraded as time goes by, in addition to change in colors of the mixtures. Furthermore, the bottled mixtures may generate floating matters and deposit therein with passage of time.
In an effort to overcome the above-described problems, the inventor of the present invention proposed cap devices for bottles, which are capable of mixing an additive contained therein with a material contained in a bottle to prepare a mixture. However, such proposed cap devices are problematic as follows. That is, when a cap body is rotated to move up relative to a mouth of a bottle and thereby to open a cavity of the cap body, a vacuum pressure is not smoothly removed from the cavity containing the additive therein. In an effort to overcome the problem, a small vent hole having a valve cock to open or close the vent hole is formed at a top surface of a cap cover assembled with the cap body into the cap device. However, when the valve cock is not timely or appropriately opened, the vacuum pressure is not smoothly removed from the cavity. In such a case, the additive cannot smoothly flow from the cavity into the bottle through a lower end of a funnel part provided in the cap body.